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<h2><a name="SECTION006310000000000000000"></a><a name="struct-objects"></a>
<br>
4.3.1 Struct Objects 
</h2>

<p>
The <tt class="module">struct</tt> module also defines the following type:

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><span class="typelabel">class</span>&nbsp;<tt id='l2h-448' xml:id='l2h-448' class="class">Struct</tt></b>(</nobr></td>
  <td><var>format</var>)</td></tr></table></dt>
<dd>
  Return a new Struct object which writes and reads binary data according to
  the format string <var>format</var>.  Creating a Struct object once and calling
  its methods is more efficient than calling the <tt class="module">struct</tt> functions
  with the same format since the format string only needs to be compiled once.

<p>

<span class="versionnote">New in version 2.5.</span>

</dl>

<p>
Compiled Struct objects support the following methods and attributes:

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-449' xml:id='l2h-449' class="method">pack</tt></b>(</nobr></td>
  <td><var>v1, v2, ...</var>)</td></tr></table></dt>
<dd>
  Identical to the <tt class="function">pack()</tt> function, using the compiled format.
  (<code>len(result)</code> will equal <tt class="member">self.size</tt>.)
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-450' xml:id='l2h-450' class="method">pack_into</tt></b>(</nobr></td>
  <td><var>buffer, offset, v1, v2, ...</var>)</td></tr></table></dt>
<dd>
  Identical to the <tt class="function">pack_into()</tt> function, using the compiled format.
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-451' xml:id='l2h-451' class="method">unpack</tt></b>(</nobr></td>
  <td><var>string</var>)</td></tr></table></dt>
<dd>
  Identical to the <tt class="function">unpack()</tt> function, using the compiled format.
  (<code>len(string)</code> must equal <tt class="member">self.size</tt>).
</dl>

<p>
<dl><dt><table cellpadding="0" cellspacing="0"><tr valign="baseline">
  <td><nobr><b><tt id='l2h-452' xml:id='l2h-452' class="method">unpack_from</tt></b>(</nobr></td>
  <td><var>buffer</var><big>[</big><var>,offset
                                              <code>= 0</code></var><big>]</big><var></var>)</td></tr></table></dt>
<dd>
  Identical to the <tt class="function">unpack_from()</tt> function, using the compiled format.
  (<code>len(buffer[offset:])</code> must be at least <tt class="member">self.size</tt>).
</dl>

<p>
<dl><dt><b><tt id='l2h-453' xml:id='l2h-453' class="member">format</tt></b></dt>
<dd>
  The format string used to construct this Struct object.
</dl>

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<span class="release-info">Release 2.5.1, documentation updated on 18th April, 2007.</span>
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